1. Field of the Invention
The present invention relates to an image forming apparatus including an operating means for designating the size of sheets for manual feeding as a device or a job, and/or a reserved printing function that accepts reservations made for subsequent image forming jobs during image formation, an image forming system, a sheet feeding source designation control method, an image formation control method, and storage media storing programs for executing the methods.
2. Related Art
An image forming apparatus is known, which includes means for designating the size of sheets for manual feeding as a device (manual sheet feeder type designating means), means for designating the size of sheets for manual feeding as a job (designating means through an operation panel), and means for designating manual feeding as a method of feeding sheets used for copying originals, and performing copying operations based on instructions given by these means (first prior art).
On the other hand, of various functions performed by an image forming apparatus, reserved copying is known, wherein a next process of inputting images is executed during printing in order to perform print jobs efficiently. Further, with respect to settings for performing printing, the conventional image forming apparatus enables users to use types of sheets requiring respective different processes, such as an OHP sheet and a thick sheet, in addition to an ordinary sheet, by providing settings corresponding respectively to such different processes (second prior art). In the conventional image forming apparatus, a print job is executed based on the user's designation of a sheet cassette through which a sheet or sheets are to be supplied.
However, the above conventional image forming apparatuses have the following problems: In the first prior art, a print job using manual feeding needs designating a sheet size for manual feeding by using the manual feeding sheet size designating means, and designating a sheet cassette by using the manual feeding designating means. When the user considers by mistake that he or she has selected the sheet cassette together with the sheet size upon designation of the sheet size, i.e. when the user has designated only the sheet size, but not the sheet cassette, the image forming apparatuses may sometimes execute the print job using sheets fed through an undesired sheet cassette.
Further, in the second prior art, as mentioned above, a print job is executed based on the user's designation of a sheet cassette through which a sheet or sheets are to be supplied. To execute a print job using a sheet or sheets from a manual feed tray mounted on the image forming apparatus, for example, the user cannot designate the size and type of sheet for printing jobs to be reserved, and determines whether or not a sheet or sheets are on the manual feed tray when he or she sets each print job. This makes it difficult for the image forming apparatus to smoothly execute different manners of printing through manual feeding (for example, printing processes including manual feeding of A-size ordinary sheets, and special sheets such as postcards and OHP sheets) according to a plurality of print jobs.